Drilling platform (3,3)
I believe the answer is:
oil rig
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">drilling platform</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this before)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for oil rig that I've seen before include "Drilling platform" , "Fuel well" , "source of offshore wealth" , "used by a bore" , "'Structure for drilling (3,3)'" .)